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DOE OSTI2018

Neutron detection

A neutron detector includes a microchannel plate having a structure that defines a plurality of microchannels, and layers of materials disposed on walls of the microchannels. The layers include a layer of neutron sensitive material, a layer of semiconducting material, and a layer of electron emissive material. For example, the layer of neutron sensitive material can include at least one of hafnium (Hf), samarium (Sm), erbium (Er), neodymium (Nd), tantalum (Ta), lutetium (Lu), europium (Eu), dysposium (Dy), or thulium (Tm).

Feller, W. Bruce↗

NASA NTRS1990

Low-Noise, Long-Life, High-Gain Microchannel-Plate Glass

Dark noise reduced substantially without degrading other properties. Glass suitable for use as active material for microchannel plates (MCP's) free of constituents including significant amounts of radioactive isotopes.

Feller, W. Bruce↗

NASA NTRS1990

Development of microchannel plates in advanced wind-tunnel instrumentation

Microchannel plate (MCP) electron multiplier dynamic range has been increased 3 to 4 orders of magnitude at ambient temperatures, through enhanced input count rate capability and reduced background or 'dark' noise. The previous upper limit of roughly 10(exp 7) - 10(exp 8) cm(exp -2)s(exp -1) at ambient has been extended to levels approach 10(exp 10) cm(exp -2)s(exp -1) under continuous dc operation. The lower limit, previously set by an irreducible background component (approximately 0.6 cm(exp -2)s(exp -1)), has been lowered to the cosmic ray limit of .01 cm(exp -2)s(exp -1). The high end improvement was achieved by conductively cooling a very low resistance MCP by bonding it to a heat sink, while maintaining pulse-counting operation with multianode readouts. The low-end improvement was achieved by removing all radioisotopes from the MCP matrix glass. The detectors will benefit optical and mass spectrometry, flow visualization, plasma diagnostics, magnetometry, and other high signal flux applications. Very low MCP background noise will benefit X-ray and UV astronomy, medical imaging, trace isotope mass spectrometry, and other applications where the signal flux is often extremely low.

Feller, W. Bruce↗